Extrusion of an apoptotic cell from an HBE monolayer as shown by confocal Z-series. This set of images shows early extrusion events (middle and late events are CIL# 37909 and 37910). The bioactive lipid sphingosine-1-phosphate (S1P) is produced by dying cells and activates actomyosin contraction in surrounding cells. The nucleus is in blue, the actin-myosin ring at the basolateral surface is in red and S1P is in green.